Carbonization of coal



RECEYlNG HOPPER W. RUNGE CARBONIZATION OF COAL Filed Nov. 6, 1924 DRlER PuLvERlzER RECEIVING HoPPER May 8, 1928.

STOEGE CKUHER Bym-f' @ad ff/s ATTORNEY I Patented -May V8, 1928.

1,669,023 UNITED STATES PATENT OFFICE#- WALTER EUNGE, or Eas'r ORANGE, NEW JERSEY, A'ssIGNoE, EY MESNE ssamm" MENTS, TO INTERNATIONAL COAL CARBQNIZATION COMPANY, A CORPORATION DELAWARE.

CARBONIZATIUN OI COAL.

Application filed. November materials analogousthereto.

The invention has numerous aspects or objects, as will hereinafter clearly appear, among which there may be mentioned by way ot' illustration and not by way of limitation the following, and it will be noted that many others might be specifically referred to at this time.

Certain aspects pertain to the treating or pretreating of coal by a hot oxidizing medium under conditions whereby the coal loses its agglutinating properties or, in other words, the tendency for the particles to adhere and stick together, but under conditions whereby the coal loses only a small percentage of its hydrocarbon volatile content;

Another aspect relates to the treating or pretreating of coal-pulverizedl coal-by a hot gaseousmedium while the fine particles of pulverized coal are suspended therein but under conditions whereby such particles retain substantially all the solid' and hydrocarbon Volatile constituents thereof prior to a subsequent processing of the coal for other puropses and while the coal is in finely divided form. n

Other aspectsrelate to the pretreating of coal` preferably in pulverized form, under conditions to destroy the agglutinating propertics or the tendency for the particles to stick together and the subsequent carbonization ot' the coal thus pretreated.

Ano-ther aspect relates to the precipitating ot coal in finely divided form through a rising oxidizing atmosphere under conditions to overcome the tendency for the particles to adhere or stickvtogether but under conditions whereby the coal loses only a small portion of its hydrocarbon volatile content, and the subsequent carbonizing or distilling ot the coal thus pretreated While precipitating through a body of rising` hot gases Further aspects relate to the treating of coal in finely divided'form, preferably when dry, through the carbonizing action ot a hot gaseous medium obtained by the. withdrawalot gases from the process and reheated to the extent desired prior to reintroducing e, 1924. 4semi No; 748,037.

gases in direct contact with precipitating coal within the carbonizing zone.

A further object which may be enumerated involves the pretreating of pulverized coal by a hot medium, as an oxidizing medium within which the finely divided coal is suspended until it has been converted into a finely divided product, the pretreated particles of which do not tend to adhere to any appreciable extent but which retain practically all ot the hydrocarbonvolatile content, and the subsequent carbonization, distillation and/or gasiiication of the coal thus pretreated while the coal is suspended in a gaseous medium hotter than that of the pretreating gaseous medium.

It will be manifest that many other aspects or objectscould beenumerated but it is not believed any further exemplification of thev objects is necessary or advisable.

The drawing accompanying this specification and which constitutes a part thereof illustrates somewhat diagrammatically an apparatus within or by which theinvention may be realized.

According to the `sole figure thereof coal from storage or a crusher 1 is conveyed to a receiving hopper?, passed to a drier 3, thence to a second receiving hopper 4 from which it passes to a pulverizer 5, thence to a third receiving hopper or storage bin 6 within which hopper dry pulverized coal is stored and from which it is withdrawn as desired.

Pretreatng retort.

ably under conditions whereby the coal will i enter the retort without permitting the enktrance thereto of any objectionable amount of cold air or the escape to the atmosphere of the hot gaseous medium from within the retort. The coal thus fed, which is manifestly in the'form of fine particles, graviveffect of the hot air under conditions whereby the coal loses its sticky or agglutinating properties but under conditions whereby the coal loses only a small percentage of its hydrocarbon volatile content and thus the coal retains substantially or practically all the solid and hydrocarbon volatile content' it originally possessed. From the bottom of the retort '9 or the receiving space 10 the treated, or pretreated coal as one may call it, is withdrawn as desired, preferably under conditions so as not to permit the entrance to the interior of the retort of objectionable coldair or the escape from the bottom of the retort of the hot gaseous medium therein.l The means for permitting this with dravval is indicated by 11 as a pair of sliding gates. The heat for maintaining the pretreating process is supplied at the bottom of the treating or pretreating zone 8; the

gaseous treating medium with'any gases en-` trained therein as a result ofthe pretreating process passes frpm the interior of the retort as through oiftake piping 12. The pretreated product is conveyed in any suitable manner as through a closed conveyor 13 to a hopper 14 leading to a second feeding means 15.

Oar-bombing retort.

The feeding means 15 is constructed so as to feed or shower the pretreated coal-Which is in finely divided form which preferably still retains a substantial part of its heat and which may still be referred to as pulverized coal although it has been treatedinto the upper portionk of ain unobstructed vertically extending carbonizing or distilling zone 16 within a retort or carbonizing chamber 17. The construction of the feeding means 15 is such as to 'supply the coal for treatment tothe interior of the retort under conditions whereby the coal will enter the retort without permitting the entrance of any objectionable amount of air or the escape to the atmosphere of the gases from within the retort. The coal thus fed or showeredwhich is still in the form of fine particles-gravities downwardly in cloud-like form but with a retarded ga'vitation toward the bottom or receiving space 18 of the .carbonizing zone 16. In transit the coal or material under treatment is distilled, carbonized and/or gasiiied by and while in supension in upwardly moving` hot gases and gradually become precipitated as a fine carbonized residue-either a partially vcarbonized residue or a completely carbonized residue as desiredupon the parts of the structure defining the bottom of the receiving space 18. From the bottom of the retort or earbonizing chamber 17 or the receiving space 18 the carbonizcd residue is withdrawn as desired without permitting the entrance of objectionable air to the interior of the retort or without permitting the objectionablelescape of gases to the atmosphere. The means for permitting this withdrawal is indicated by 19 as a sliding gate and by 20 as a screw conveyor. The heat for maintaining the carbonizing process is supplied' at the bottom of the carbonizing or distilling zone 16, as will hereinafter more clearly appear. The gases of, or resulting from, the carbonizing or distilling process pass from the carbonizng zone; or, in other words, from the interior of the retort as @through offtape piping 21 to any suitable gas purifying"` apparatus indicated as at 22; thence to'holder 23 from which it is drawnl as desired through pipe 24 and valve controlled pipes 25 and 26, the latter of which leads to a burener 27 for-supplying heat to a heat interchanging device 28.

j Heating systems for the retorts.

Eaeh retort and its function has in a general Way been described. The heating system for each will now bevdescribed. Reference has heretofore been made to the members 19 and 20 ,as controlling the withdrawal of the carbonized residue from the carbonizing zone 16. lIt will hereinafter appear that the process carried out in the carbonizing zone 16 is at a considerably higher temperature than that carried out in the pretreating zone 8. In other words, the carbonized residue from the zone 16 is comparatively hot and has a considerable residual heat which can be employed to good advantage in the pretreating zone 8. According to the construction shown the carbonized residue passes into a dry coke cooler 29 and the heat from the carbonized residue therein is indirectly transferred to air entering the coke cooler at 30 and leaving by pipe 31. If this air is sufficiently hot, that is has a temperature of approximately 800 F. (800 degrees Fahrenheit), then it is introduced directly into the bottom or lower portion of the retort 9 or, in other words, at the base or lower Aportion of the pretreating zone 8. If, however, the air thus supplied is not soufliciently hot enough, then it is supplied as through a heat inter'changing device 32 which is heated in any suitable manner as by burner 33 supplied with the gas of at pipe 34, which afterfbeing heated passes throuofh valve controlled pipe 35 into the pipe leading to the bottom of the retort.

"the process and this heats the air entering The products of combustion from the burner 33 pass from the heat interehangmg device 32 as by pipe 36.

fof the retort but it can be supplied to nreceiving space or spaces 37 defined in and by the walls of the retort whereby said walls` can be heated and maintained at the proper temperature desired.

Referring now to the heating system of the carbonizingretort,,the burner 27 aspreviously indicated supplies heat to the heat interch'anging device 28 and the products of combustion pass to the atmosphere by pipe 38. Gas for efl'ectingvthe earbonizing process within the carbonizing zone 16 can by valve controlled pipe be supplied to and through the heat interchanging device 28 and when reheated to the extent desired it is supplied by means of pipe 39 to the lower portion of the 'carbonizing retort 17 or, in other words, at the base or lower portion of the carbonizing zone 16. If desired, hot gas eanalso be supplied to the space or spaces 40 defined in and by the walls of the retort 17 whereby heat can, at will, thus be added lor supplied for maintaining the desired temperature, or het gas may even be introduced directly into the carbonizing zone 16, as through pipe 41;

According to the preferred mode of realizing or utilizing the invention the coal is subjected to a two stage process one of which stages is carried out in a preheating or pretreating retortv and the second ofl which stages is carried out in the carbonizing retort and which are arranged and connected so that the preheated material preferably passes to the carbonizing retort with a substantial amount of the heat therein; in other words, while the material is still in a relatively hot condition.v It will be realized y Ier cent. Moisture 1.5' Volatile matter 34 (hydrocarbons) Fixed carbon 57.5 Ash 7,

and having a fineness indicated'by the following: y

these two retorts might in effect be embodied in a single construction with a preheating section arranged above the carbonizing seetion. l

Referring now to the process in detail, coal in finely divided form is conveyed or showered into the upper zone of the pretreating or preheating retort and it gravitates toward the bottom thereof. During its downward passage it encounters rising hot oxidizing gases, to wit, air.4 This air is previously heated to approximately 800o F., enters the bottom of the preti-eating retort at approximately said temperature, slowly flows toward and into-the upper zones of the retort, and leaves the upper portion of the retort at approximately 500 F.; in other words, the Coall in its downward or gravita- -tive passage is subjected to the retarding action and effect of the upwardly fiowing gases-air-having an average temperature of approximately 650 F. The retardation of the precipitation offthe coal by the upward flow of the air-is such that the coal particles are `held in `suspension approximatel 30cseconds or, in other words, long enoug 1 -for the coal to attain a temperature of approximately 600o F.to700 F. by the time it is precipitated at the bottom of the retort and the heat is suieient to effect a removal of substantially all of the moisture and only -`a small portion of the hydrocarbon volatile materials in the coal, and to cause the coal to lose practically allvof its agglutinating or sticking together qualities. It will, therefore, be seen vthat the coal thus precipitatedl falls as fine particles slightly enlarged above the size in which it was originally fed or showered because of the pretreatment and such oxidizing as is encountered within the retort. A specific example of coal thus treated in such a preheating or pretreating retort is typified as follows.

Coal having the following analysis- Y This coal is sometimes referred to as high volatile coal.

(A wire screen having 40,000 openings per 59% passed through a 200 mesh screen .isquam inch). l

has been fed into a preheating retort having a treating zone of approximately 30 feet in height. The air for treating the coal was introduced .at a temperature of approximatelyv 800 F., caused to pass upwardly through and in contact with the gravitating coal until the air` left the retort at approximately 500o F. and conveyed heat to the coal so that thecoal has when precipitated a temperature of approximately between 600o F. and 700 F. or, in other words, was subjected tothe oxidizing and heating action of the air at an average temperature of 650 F. The particles thus treated had ari actual slight increase in size, as shown by the following,

38% passed through a 200 mesh screen Vhile the above indicates the type of treatment which may be carried out in this preheating chamber, it will be noted that the treatment and the resultant product will dej pend to a large extent upon the characteristics of the coal and of the thermal and chemical efects desired as a result of the pretreatment.

The pretreated coal is preferably conveyed while still hot to the carbonizing retort. There may be a slight loss of heat from the time of its accumulation, during its transfer, to the time of feeding into the carbonizing retort.

The coal fed into the upper zone of the carbonizing retort is showered so as to precipitate through an upwardly moving body or volume of hot gas or gases which is or are relied upon .to perform the carbonizing operation within the retort. This carbonizing retort may be, for example, 50 feet high and of such diameter as may be determined and is supplied by hot gases introduced within the carbonizing zone under conditions whereby gas or gases from a-zone having a temperature of approximately 1100 F. to 1500o F. at the bottomk rise or rises in contact with the precipitating coal` and finally there leaves the retort at thejupper portion thereof the gaseous products` of'the process at an approximate temperature of 550 F. to 850 F. In other words, the gravitating particles are subjected to a hot gaseous medium having average temperatures approximating between 825o F. and 117-5o F. or an average of this, to wit 1000 F. In a vacuum it would take roughly between one and two seconds for the coal particles to drop through a space of 30 feet. to 50 feet. The rising current of gaseous medium in the carboni`zing retort retards the fall of the particles being treated so.

that in effect they are suspended in the gaseous medium approximately thirty seconds sometimes more, sometimes less; This allows sufficient time with particles of the size indicated to become suliciently heated so as to devolatilize the particles to a substantial extent. Practice has shown that by withdrawing coal of the character indicated, as

` the result of the pr'eheating operation when subjected in a carbonizing retort of the height indicatedvand to gaseous mediums of the temperatures indicated there 1s produced' a partially distilled residue having the following characteristics. Approximate lanalysis:

` Percent.

Moisture 0 'Volatile mattei' 12 Fixed carbon 78 Asli 10 and having a ineness indicated by the following- 7 passed through a 200 mesh screen The residue from this carbonizing process was not agglutinated during the carbonizing process; nor did it assume a sticky condition when precipitated. In fact the saine material was of a character which, if subjected to a carbonization direct from its raw state to the desired degree of devolat-ilization, would have developed objectionable agglutinating characteristics which would have followed 'to the end and been found as lumps or agglomerations in the resultant products. The preheating treatment previously described was simply to and actually did overcome said objectionable feature.

The heat for carrying out the carbonizing treatment may be realized by supplying a controlled and limited amount ofair into the lower zone of the carbonizing retort so as to support av partial combustion in said lowerzone; for example, according to the ducing the reheated gases into the lower zone of the retort at temperatures approximating between 1100o F. and 1500 F. and continuing the operation while withdrawing surplus gas land conducting it to the holder or otherwilse using the same as may be founddesira e. gases for performing or affecting the carbonization process--be they the hot products resulting from-combustion or the reheated gases obtained from the process-are gases which are substantially chemically inert with respect to the coal undergoing carbonization. Some of the gas may be used if desired for /preheating the air used in the pretreating process. A.- fair estimate of the solid and gaseous products made and used in the process is indicated somewhat as follows:

It will benoted that-in event the hot llt) For each ton of material fed into the upper portion oi' the carbonizing retort and subjected to carbonization by gaseous medium having an average temperature of upwardly 1000 F. there are produced from the coal approximately 3500 cubic feet of gas having a B. t. u. value of 800 B. t. u. per cubic foot and there are used in the process for preheating purposes approximately 1500 cubic feet of gas having a B. t. u. value of 800 B. t. u. per cubic foot, leaving a sulplus of 2000 cubic feet of the same type of gas for each ton of coal treated. This is in addition to condensible gases removed in the form of liquids.

According to the apparatus shown the as that is used for performing the carbonizmg process is, as above indicated, first subjected to suitable purification apparatus, indicated at 22, in which it is freed of the oil, tar, etc., as is customary -in gas practice. The cool, clean gases are divided. Some go to the holder or other place of use while some are used in the carbonizing retort after assing through a heat .interchanger 28 w -ch superheats them to the desired temperature of approximately 1100 F. to 1500 F. Within the carbonizing 'retort the superheated as performs the carbonizing process prevlously described.

1n the form of apparatus shown, it is pos-` sible to pass air through the dry coke cooler or heat vinterchanger 29 at the bottom of the carbonizing retort so that the air absorbs some of the heat from the coke and the air thus to a certain extent is preheated and passes. directly to the pretreating chamber 9; or, it may be passed into an air heater or heat interchanger 32 for bringing the air up to the desired temperature of approximately 800 F. and from lthis source lthe air is supplied to the interior ofthe pretreating retort where itI performs the process previously described.

What I claim is:

1. A method comprising subjecting coal in finely -divided form to carbonization by feeding it into the upper portion of -a carbonizing zone, within which zone the coal precipitates counter to and in direct contact with an upwardly movin gaseous medium that delays the settling o the precipitating coal and which is hot enough to carbonize to the desired extent the precipitatingcoal, and collecting the coalv as partially carbonized residue, said hot gaseous medium being created and maintained by and from gases withdrawn from the process and thereafter' cooled and purified and some of which are' thereafter reheated to between 1150 F. and 1500 F. and returned in reheated condition into the lower portion of the carbonizingv zone to create the upwardly moving gaseous medium.

2. The arboniizing of on by the method bonizing zone an which comprises feeding dry finely divided coal into the to of a carbonizing chamber and causing` a ela ed precipitation of the finely divided coal by hot gasescaused by the introduction to the bottom of the carbonizing chamber of gases of the process indirectly reheated to between 1150o F. and 1500 F., withdrawing from the top of the carbonizing chamber gases resulting from the process at approximately 550O F. to 850F., and collecting the partially carbonized residue resulting from this process.

3. The carbonizing of coal by feedin finely divided coal into the top of a define carbonizing zone and eecting a delayed precipitation of the finely divided coal by a counter current of hot gases caused bythe introducing at the base of the carbonizing zone of gases of the process reheated to u wardly of approximately 1150o F., wit drawing from the top of the retort ofy gases resulting from the process, cooling and purifying said withdrawn gases, reheating some of said. cooled purified gases and thereafter returning the reheated gases to the carbonizing' zone forefl'ecting the carboniz'ing operation, and collecting as partially carbonized coal the precipitated residue resulting from the process.

4. The process of carbonizing coal comprising showering pulverized coal from within the upper ortion of a confined carcausing a delayed precipitation of the inel divided coal by hot gases moving upwar ly because of the in troduction to the bottom of the carboxiizing zone of gases withdrawn from the process.

and indirectly heated prior to such introduction, withdrawing from the top of the retort gases resulting from the process, indirectly reheating to between 115()o F. to 15000 F. some of the withdrawn gases and reintroducing them into the bottom of the carbonizing zone for the purpose outlined, collecting the partially `carbonized residue in a receiving space below the carbonizirlg a counter current of loo zone and into which Space the vpartially carbonized residue gravitatesfrom the carbonizing Vzone, and'withdrawing precipitated. partially carbonized residue from said receiving space.

5. The method which comprises subjecting coal in finely divided form to carboniza- .tion by iiowing hot gases within which the coal is -suspended while being carbonized, withdrawing gases of the rocess, indirectly reheating some of the wit drawn gases u wardly of 1150 F. but not substantial y above'1500o F. and returning said reheated gases tothe process for maintaining the owing hot gases necessary for the process,

nd collecting the resulting carbonized resi- 6. The process comprising subjecting finely divided coal having agglutinating properties in suspension to the effects of .a hot oxidizing gaseous medium for destroyingpthe agglutinating properties of the coal and until the agglutinating properties have been destroyed but under conditions whereby the coal retains substantially all the solid and hydrocarbon` content of the coal and whereby the coal loses at the most only 4a. small percentage of its hydrocarbon volatile content, and thereafter carbonizing the still finely divided coal while in suspension in hot gases which are chemically inert with respect to the coal.

7, The method comprising preliminarily subjecting pulverized coal having agglutinating properties to hot air by suspending the coal in the hot air until the coal loses its agglutinating properties and v loses of its volatile contentl only a small percentage thereof and so that the coal retains its finely divided state, and finally subjecting they coal to carbonization in hot gases chemically inert with respect t0 the coal and under conditions to leave a finely divided carbonized residue. f

8. The treating of prising agglutlnating characteristics in and subjecting it to 4heated air until the coal particles coal by the process com- `have attained a temperature of approximately 650 F. and have lost their agglutinating characteristics and thereafter in a non-oxidizing atmosphere subjecting the coal to carbonization.

9. The method comprising in one retort subjecting finely divided coal having agglutinatin properties to' hot oxidizing gases until t e coal loses its agglutinating prop-V erties but under conditions to remove only a. small percentage of the hydrocarbon vola'- tile content of the coal and thereafter in another retort subjecting the coal while finely divided and in suspension in hot gases chemically inert with respect to the coal to carbonization so as to distill off a substantial percentage of. the hydrocarbon -volatile contentn of the coal but under conditions to leave a finely divided carbonized residue.

10. The method comprising feeding pulverized coal havingY agglutinating properties into a-pretreating zone and subjecting the pulverized coalinand to hot gases until the vcoal has lost its agglutinating properties and under temperature conditions so that the coal loses only alittle of its hydrocarbon volatile content, and thereafter transferring the coal to a carbonizing zone andtherein suspending and subjecting the coal in and to hotter ases and under conditions so that much 0% its hydrocarbon volatile content is distilled off and so as to leave the solid carbonized residue in nelyydivided form.

suspending pulzerized coal having p Leashes the action of aihot oxidizing medium while' the coal remains'suspended in the hot oxidizing medium until the coal has lost its agglutinating or adhesive properties and thereafter in a carbonizing chamber or retort subjecting the coal thus treated and while still in finely divided form to a carbonizing action.

12. A process which comprises subjecting finely divided coal having agglutinatingr properties and havin a high hydrocarbon volatile content and W ich is in suspension in a hot oxidizing atmosphere to the action thereof under conditions whereby the coal loses only a small portion of its volatile content but until it has lost its agglutinating properties, separately removing the coal thus pretreated on one hand and the gases for and resulting from the pretreating operation on the other, thereafter subjecting the coal thus treated but while still in finely divided condition to a carbonizing action of another hot gaseous medium which is chemically inert with respect to the coal with the coal in susension therein under conditions whereby the coal thus treated loses a substantial portion of its volatile content and is converted into finely d/iyided'carbonized residue, and separately removing the resulting carbonizing coal residue on the one hand and the said last mentioned gaseous medium and the gases resulting from the carbonizing action on the other and in such manner that the last mentioned gases are not mingled with the gases for or of the pretreating operation.

13. The method which comprises suspending and subjecting pulverized coal having agglutinating properties to the action of hot cally inert with respect to the coal and suiii- 4ciently hot to effect a desired carbonization of the coal in suspension, collectingl the gases ofthe carbonization process, and withdrawing the resulting finely divided carbonized residue precipitated from the carbonizing zone.

,l 14. method comprising subjecting dry pulverized coal having agglutinating properties to pretreatment by subjecting it to the action of hot gaseous mediums under condi- 'tions by which the coal loses its agglutinat mg properties but so as\to leave vin the prel treated coal'substantially all of its original 11., The treating of coal by the method comprising feeding coal which is in finely, di`

hydrogen volatile content, thereafter passing the finely divided pretreated c oal to the upper portion of a carbonizing zone downwardly Within which the coal thus fed precipitates counter to and in direct contact with an upwardly moving liot gaseous medium that is substantially chemically inert with respect to the coal and which delays the settling of the precipitating coal and which is hot enough to and does carbonize to the desired extent the coal while precipitating, and collecting the resulting coke residue.

15. The method which comprises subjecting pulverized coal having sticky characteristics that develop when heated by suspending the coal in a hot oxidizingniediuni to the action thereof under conditions to cause the coal to lose its tendency for the particles to adhere to each other, conduct-ing the coal thus tieated to a hot caibonizing zone and therein subjecting the coal to the action of a gaseous medium suiiciently hot to eliect a 'desired carbonization of the coal and within which the coal is suspended until the desired carbonization is realized, withdrawing the gases'of the process, reheating some of the i "withdrawn gases and returning the reheated gases to the interior of the carbonizing zone v to provide the hot gaseous medium for maintaining tlie process, and withdrawing at will the carbonized residue resulting from the process.

16. The method comprising precipitating 'and subjecting pulverized coal having agglutinating properties into and to the action of hot air having an average temperature of approximately G50 F. under conditions that the coal comes to a temperature of approximately 650 F. but under conditions whereby thecoal while in contact with the air -loses its agglutinating properties but little of its volatile content, thereafter subjecting the coal to carbonization by a low temperature distillation process, withdrawing the gases of the low tempel-ture distillation from the distillation zone, and also withdrawing the carbonized residue resulting from the low temperature distillation.

17. The method comprising feeding pulverized coal having agglutinatinv properties and with a substantial hydrocar on volatile content into the top of a pretreating chamber, and subjecting it while precipitating to a counter flow of a hot gaseous medium maintained by continuously feeding air into the bottom of the pretreating chamber at a temperature of approximately 800o F;, continuously withdrawing the gaseous medium' from the top of the pretreating chamber at a temperature'of 500o F. and subjecting the pretreated coal to carbonization.

18. The treating of coal by the method which comprises precipitating pulverized coal having agglutinating characteristics through vrising hot air having temperatures approximately between 500o F. and 800O F. and until the coal has a temperature of approximately 650 F., thereafter causing precipitation of the coal while still in linely divided condition through an upwardly flowing hot gaseous medium so `as to effect carbonization while in suspension in thel gaseous medium, said gaseous medium having linal temperatures between 500o F. and 800 F. and initial temperatures of between 1150O F. and 1500O F., and collecting the resulting residue in finely divided form.

19. lhe method which comprises suspending pulverized coal having agglutin-ating properties in hot air and subjecting the suspended coal to the action of the hot air until the pulveii'f1ed coal has lost its agglutinating properties but under conditions that the coal loses only a small percentage of its hydrocarbon volatile content, conveying the coal thus pretreated and which is still finely divided and while still hot to a carbonizing zone and therein suspendingl the pretreated coal in a gaseous medium which is hotter than the air, and subjecting the suspended, pretreated coal to the action of the hotter gaseous medium until a substantial percentage of the hydrocarbon volatile content of the coal is distilled olf, withdrawing gases from the carbonizing zone, and withdrawing the resulting finely divided carbonized residue. e 20. A method comprising feeding dry pulverized coal having agglutinating properties into the top of a pretreating retort within which the coal thus fed precipitates counter to upwardly moving hot air and permits and causes delayed settling of the precipitating coal particles until the coal has become heated to approximately 6500 F. and has lost the properties whereby the particles adhere or stick together, causing the finely eous medium is hot enough to carbonize to the desired extent the precipitating pretreated coal, and collecting the precipitated carbonized residue.

21. The method comprising feeding pulverized coal having agglutinating properties into thetop of'a confined pretreating zone and subjecting it to a lcounter current of a hot gaseous medium maintained by feeding air into the bottom of the pretreating Zone at a temperature of approximately .,800o F. and withdrawing the gaseous medium from the top of the pretreating zone at a temperature of 500 F., thereafter subjecting the pretreated coal in finely divided form and while precipitating through a confined carbonizing zone to a counter current of upwardly flowing hot gaseous medium having a temperature at the bottom of the carbonizing zone of between 1150 F. and 1500 F., withdrawing ases of the process from the top of the car onizing zone at temperatures between 550 F. and 850 F. and collecting the resulting carbonized residue.

22. The process of treating coal Withhigh volatile content and having agglutinating characteristics which comprises pulverizing the coal-until at least 50% will pass through 9,200 mesh screen and so that all of it will pass through a 30 mesh screen, showering the coal through a hot zone whilesubjecting it to a rising current of hot gaseous methrough a hot zone while subjecting it to a 20 rising current of hot gases having an average temperature of approximately 1050 F. and under conditions whereby the coal will remain suspended in the hot gases approximately 30 seconds, and collecting the finely 25 divided residue resulting from the process;

In wltness whereof I have hereunto signed my name. f

WALTER RUNGE. 

